Near the town of Bonito, Brazil is where you’ll find the “Gruta do Lago Azul”. It is a subterranean lake. The lake has a circular opening above it with a diameter of about 40 meters (that’s 130 ft). The opening allows for sunshine to come in and illuminate the waters of the underground lake. The months between September and February is when you’ll find the best lighting. During those months, the lake takes on an incredibly intense blue color (hence the name).

On top of witnessing its beauty, visitors who look closely through the water might be able to spot fossilized bones of mammals that lived in this region in the Pleistocene period that began about 1.8 million years ago and lasted to just about 11,700 years ago!

Imagine this. You’re standing above an opening on the surface of the earth looking down to a deep-blue underwater lake. You look through the water only to see the bones belonging to giant sloths, armadillos and sabre-toothed tigers!

Sounds like a trip of a lifetime, right? Below are some people who visited the location and Instagrammed about it.

Finalizando o nosso passeio na belíssima Gruta do Lagoa Azul. #matogrossodosul #bonito #grutadolagoazul #??

A post shared by Nilmar Fernandes (@nilmar_fernandes) on

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